An internal combustion engine carburetor normally has a choke mechanism which provides an enriched part throttle air-fuel mixture during cold engine operation. The choke mechanism normally also operates certain supplementary controls such as a fast idle cam to limit closure of the carburetor throttle during cold engine operation and a latch to prevent opening of the secondary air valve during cold engine operation.
On at least one other occasion, it was proposed that the choke mechanism be used to maintain a stoichiometric air-fuel mixture during warm engine operation as well as provide an enriched mixture during cold engine operation. However, no provision was made for control of other carburetor functions in a desired manner.